Piston



F. MALINA PISTON Oct. 24, 1939;

Filed Feb. 25, 1938 2 Sheets-Sheet l Oct. 24, 1939.

F. MALINA 2,177,574

PISTON Filed Feb. 25, 1938 2 Sheets-Sheet 2 manufacture. tion.

Another object of the invention resides in the In the drawings in which like charactes of refprovision of a piston having a laterally extending erence designate corresponding parts: annular integral partition wall spaced from the Figure 1 is a side elevation of a pis o y- 30 top of the piston head and located substantially s the invention 30 at the lower portion of the piston head and pro- F 2 is a S de elevation of the piston Viewed at vided with a pair of oppositely disposed upwardly right an es to and outwardly bevelled arcuate margins cooper- Fig. 3 is a vertical sectional view taken on the ating with a pair of spaced similarly bevelled line 3-3 of Fig. 2. arcuate top faces .of two oppositely disposed skirt 4 s a Similar View taken on the e 35 portions to thereby provide an arcuate slot of Fi which functions to separatethe piston skirts from F g- 5 s a bottom V Of the P the piston head and ermit the passage of the F 6 s a sim ar v w of a pi n h wi a lubricating oil and enable the same to reach the mo fic 0f t Skirt Supporting a s d he 40 cylinder wall at points below the lowest oil ring on reinforcing webs or flanges. 40 the upstroke of the piston. A construction of this F s a pl n view of n f the s a n in s. character preferably includes the formation of a g- 8 is a enlarged fragmentary C s S ct on small arcuate rim-like wall disposed at the bothr h th se in ri retaining p r i n of th torn face of the lateral partition wall and at its pis n head showing a fragm y portion of t 45 juncture with the lower end of the bevelled marcy Well and e p 0 he sealing rings. 45

Patented Oct. 24, 1939 2,177,574

PISTON Frank Malina, Omaha, Nebr., assignor to Circle Motor Corporation Application February 25, 1938, Serial No. 192,665

8 Claims. (01. 309-41 The invention relates to pistons particularly Another object of the invention is to provide adapted for internal combustion engines and for each wrist pin boss a pair of reinforcing webs especially to pistons'formed of light weight metor flanges of substantially triangular shape disals or alloys. posed relatively angularly to one another and 5 One of the objects of the invention is to proformed integrally with the lateral annular partivide a piston of novel construction adapted to be tion wall and the skirt connectin Well- These cast of light metal alloy which will operate efreinforcing Webs or flanges not only reinforce the ficiently at varying temperatures in an engine connection between the wrist pin bosses and the cylinder. piston head but they also function as heat dissi- 10 Another object of the invention is to provide a pators by transferrin some Of the heat in the 19 piston of this character in which the heat will be piston head to the skirt connecting walls and distributed directly to the piston rings and cylinthey also tie the wrist pin bosses to the horizontal der Wall and only indirectly to the wrist pin partition wall and control the wrist pin boss exbosses and in which'the wrist pin bosses will have p on maintain t W s P bosses in p p uniform expansion and contraction and will alalignment at all times. 15

ways be maintained in alignment, With these and other objects in view, the in- Another object of the invention is to provide a vention consists in the construction and novel piston provided at the head with an interiorly comb na ion and a a t of parts he e arranged horizontal annular partition and havaf er fu ly described, illustrated in the eoeoming means for tying the wrist pin bossesto the pany drawings and pointed out in the claims 20 partition thereby providing a structure of the hereto appended, it being understood that various requisite strength adapted to dissipate heat and changes in the ferm. proportion and details of capable of being cast by a'readily removable construction, within the scope of the claims, may a single piece core and characterized by simplicity be resorted to without departing from the spirit and sturdiness of construction and low cost of or sacrificing any of t antages of the inven- 25 gin which prevents the oil from excessive splash- In the embodiment of the invention illustrated ing directly to the outer face of the cylinder wall. in i 1 t inclusive, the piston generally indi- Another feature of the invention resides in the cated by the numeral It! comprises a head portion provision of a piston provided with spaced wrist or piston head II, a pair of opp y disposed pin boss supporting walls having their upper ends laterally and longitudinally elongated skirt por- 50 formed integrally with the lateral annular partitions [2, and two wrist pin bosses I3 formed intion wall and their side portions disposed in an tegrally with two inwardly offset wrist pin boss oppositely outward direction diverging towards uppo ing Wa s l4 formed integrally With the the outer ends of the wrist pin bosses to enable vertical side edges of the skirt portions I2. the piston to be provided with wider skirts. The piston head II consists of a top wall I5, 5

2 V a vertical peripheral side wall I6 and a laterally extending annular partition Wall H. The vertical peripheral side wall I6 is formed integral with the top wall I5, and the lateral extending annular partition wall I1 is formed integral with the lower portion of the side wall IS. The top wall I is preferably reinforced at its inner or lower face with a transverse rib I8 disposed in substantial parallelism with the longitudinal axis of the wrist pin bosses I3, and preferably of approximately segmental form in longitudinal section, as clearly illustrated in Fig. 3 of the drawings. The reinforcing rib I8 is rounded transversely at its longitudinal edge and its side faces are preferably fiat, as clearly shown in Fig. 4 of the drawings.

The piston head side wall I6 is provided with a sealing ring groove I9 adopted to receive any suitable type of compression or fire ring, such as a cast iron sealing or compressionring. Below the groove I9 the side wall I6 of the piston head is provided with a plurality of narrow closely spaced sealing ring receiving grooves 20, arranged at an inclination and extending upwardly and outwardly at an angle to the transverse axis of the piston, but the said grooves may be arranged either horizontally or at a downward and outward inclination, as shown, described and claimed in an application filed by me on the 25th day of February, 1938, Serial No. 192,664. 7

Each of the narrow grooves 20 is adapted to receive a thin resilient sealing ring 2I constructed of thin ribbon-like resilient metal bent edgewise in circular form and dished when the grooves are inclined, as shown in Figs. 3 and 4, and flat when the grooves are arranged horizontally, as fully explained in the aforesaid application, and as the construction and arrangement of the grooves 20 and sealing rings 2| are claimed in the aforesaid application, no claim is made to such subject matter in the present application.

As explained in the aforesaid application, each of the sealing rings 2| snugly fits in its associated groove which has imperforate walls, and which are adapted on the upward stroke of the piston to carry suflicient lubricating oil to lubricate the cylinder wall 22.

The wrist pin bosses I3 are formed integral with the intermediate portions 23 of the boss supporting walls I4, and the said intermediate portions 23 of the walls I4, as illustrated in Figs. 2, 3, 4 and 5 of the drawings are formed at, their upper end portions integral with the lower face of the transverse annular partition wall IT. The side portions 24 of the boss supporting walls I4 are disposed at an angle to the intermediate portion 23, and diverge outwardly to provide pockets or recesses exteriorly of the interior of the piston for the wrist pin bosses which are located within the exterior pockets or recesses provided by the walls I4, and also within the circumferential limits or circle defined by the piston head so that there will be no liability of the bosses accidentally contracting with the cylinder walls. The particular construction of the walls I4 not only provide ample clearance for the bosses I3, but they also enable the piston to be provided with wider skirt portions I2, and facilitate circumferential expansion of the skirt portions I2 which are formed integral with the outer diverging side portions 24. The walls I4 having the intermediate portions 23 and the side portions 24 serve to support the skirt portions I2 as well as the wrist pin bosses I 3, and

in order to control the expansion and contraction of the wrist pin bosses and maintain the same at all times in alignment, the Wrist pin bosses and the intermediate portions 23 of the walls I4 are tied to the horizontal partition wall I"! by reinforcing webs or flanges 25 of substantially triangular shape disposed in pairs at the upper portions of the walls I4 and arranged at an angle to each other, and to the intermediate and side portions of the walls I4 and also to the longitudinal axis of the wrist pin bosses and diverging inwardly. The reinforcing webs or members 25 are formed integral with the lower face of the horizontal annular partition wall I1, and with the intermediate and side portions of the walls I4 at the corners formed by said side and intermediate portions of said walls I 4, and

they reinforce the wall connection between the wrist pin bosses I3 and the piston head II, and at the same time, function as heat dissipating walls by transferring some of the heat from the piston head to the skirt connecting the boss supporting walls I4. The horizontal wall partition I1 and the triangular webs or members 25 avoid any direct connection of the boss supporting walls with the top wall of the piston head, and the horizontal partition wall forms an air chamber between the top wall of the piston head and the wrist pin bosses so that the intense heat of the piston head is conveyed away by the piston rings and the cylinder walls, and the remaining portion of said heat is dissipated by the triangular webs or members 25. By the aforesaid construction and arrangement the piston bosses are relieved of the intense heat to which the piston head is subjected, and expansion and contraction of the wrist pin bosses is reduced to a minimum, and at the same time the wrist pin bosses are maintained in alignment at all times, and lateral binding of the wrist pin bosses on the wrist pins is prevented.

Instead of employing the angular arrangement of the boss supporting walls I4 and the reinforcing and expansion controlling webs or members 25, the skirt connecting walls 26 may be curved and the reinforcing and boss expansion controlling webs or members 21 may be curved, as illustrated in Fig. 6 of the accompanying drawings. The skirt connecting and boss supporting walls present outer concave faces and inner convex faces while the webs or members 25 diverge from each other and from the side portions of the walls 26 and also from each other. The curved skirt connecting and boss supporting walls 26 and the reinforcing and boss expansion controlling webs or members 21, function substantially the same as the walls I4 and the webs or members 25 heretofore described.

The wrist pin bosses are preferably reinforced by fillet plates 28 arranged in pairs, as clearly illustrated in Fig. 2 of the drawings, and in pistons of the heavy duty type additional reinforcements of the bosses may be provided by horizontal fillets 29, but the latter may, of course, be omitted when not required. The piston skirts progressively taper in thickness downwardly from their upper edges to their lower edges, and the supporting walls which connect the piston skirts are preferably tapered at their lower portions below the wrist pin bosses.

The lower portion of the piston head II at substantially the periphery or marginal side of the horizontal annular partition wall I! is cut at 30 at a sharp angle to separate the upper edge of the skirt portion I2 from the piston head H, to provide an upwardly and outwardly inclined 'slot or channel 3| extending arcuately of the piston from one side edge of theskirt portions to the other side edge thereof, and also between the upper ends of the side portions of the walls I 4 and the annular horizontal partition wall H. The channels prevent direct transfer of heat from the piston head to the skirts of the piston, and also provide passages to permit the lubricating oil to pass from the interior of the piston to the cylinder wall below the lowermost ring during the upward stroke of the piston.

The piston head is provided at the slot or channel 3| with a depending rim-like arcuate wall 32 consisting of a flange projecting from the lower face of the horizontal partition wall H at the lower end of the piston head, to prevent oil from excessive splashing directly through the slot or channel 3| on to the outer pistonwall. The piston skirts and the upper edges of the side portions of the boss supporting walls M are bevelled or inclined at 33 at the ends of the slot or channel 3|. The bevelling of the piston skirts and the upper ends of the side portions of the wrist pin boss supporting walls, form tapered portions at the top of the piston skirts.

The surface of the piston skirts, the boss supporting walls and the reinforcing and expansion controlling webs or flanges, are vertical or in parallelism with the longitudinal aXis of the piston, so that the piston structure from the horizontal annular partition to the lower end of the piston may be cast with a single piece core, and the core may be pulled without collapsing or previous removal of any portion thereof, thereby materially reducing the cost of manufacture of the piston. The interior of the piston above the horizontal annular partition wall may be formed by a sand core, and the opening in the annular horizontal partition wall may if desired, be plugged to form a dead air chamber or it may be left open, if desired.

What is claimed is:

l. A piston including a piston head comprising a top wall, a depending peripheral wall and an annular partition wall extending inwardly from the peripheral wall and spaced from the top wall, supporting walls depending from the piston head and having outwardly diverging side portions forming exterior pockets, aligned wrist pin bosses located wholly withiln said pockets entirely exteriorly of the piston and formed integral with said supporting walls, circumferentially spaced piston skirts having their side edges integraly connected to the outer side edges of the diverging side portions of said supporting walls, and reinforcing and temperature controlling members formed integral with the wrist pin bosses and the annular partition wall and tying the said parts together and maintaining the wrist pin bosses in alignment at all times.

2. A piston including a piston head comprising a top wall, a depending peripheral wall and a transverse partition wall extending inwardly from the peripheral wall and spaced from the top wall, vertical supporting walls depending from the piston head and having exterior pockets, aligned wrist pin bosses arranged in said pockets wholly exteriorly of the piston and formed integral with said supporting walls, circumferentially spaced piston skirts having their side edges integrally connected to the side edges of said supporting walls, and pairs of vertical reinforcing and expansion controlling webs formed integral with the bosses, the vertical walls and the transverse partition wall and tying the said parts together and maintaining the bosses in alignment at all times.

3. A piston including a piston head comprising a top wall, a depending peripheral wall and a transverse partition wall extending inwardly from the peripheral wall and spaced from the topwall, vertical supporting walls depending from the piston head and having outwardly diverging side portions forming exterior pockets, aligned wrist pin bosses located in the pockets wholly exteriorly of the piston and formed integral with the supporting walls, circumferentially spaced piston skirts having their side edges integrally connected to the outer side edges of the diverging side portions of the supporting walls, and inwardly diverging vertical reinforcing and expansion controlling members formed integral with the vertical walls and the piston head and tying said parts together and maintaining the bosses in alignment at all times.

4. A piston including a piston head comprising a top wall, 21. depending peripheral wall and a transverse partition wall extending inwardly from the peripheral wall and spaced from the top wall, vertical supporting walls depending from the transverse partition wall and having exterior pockets, aligned wrist pin bosses arranged wholly within said pockets and formed integral with the supporting walls, circiunferentially spaced piston skirts having their side edges integrally connected to the side edges of the supporting walls, and vertical reinforcing and expansion controlling members consisting of webs formed integral with the transverse partition wall and with the supporting walls and arranged at an angle to the side portions of the supporting walls and diverging from the same and from each other and maintaining the bosses in alignment at all times.

5. A piston including a piston head comprising a top wall, a depending peripheral wall and an annular transverse partition wall extending inwardly from the peripheral wall and spaced from the top wall, vertical supporting walls depending from the transverse partition wall and having outwardly diverging side portions forming exterior pockets, wrist pin bosses formed integral with the supporting walls and arranged wholly within said pockets and exteriorly of the piston, piston skirts connecting the supporting walls, and substantially triangular reinforcing and temperature controlling members formed integral with the annular partition wall and with the supporting walls and tying the said parts together and maintaining the bosses in alignment at all times.

6. A piston including a piston head comprising a top wall, 2. depending peripheral wall and an annular partition wall extending inwardly from the peripheral wall and spaced from the top wall, vertical supporting walls depending from the annular partition wall of the piston head and having outwardly diverging side portions forming exterior pockets, wrist pin bosses arranged in the pockets and disposed exteriorly of the piston, and piston skirts connecting the vertical supporting walls, said piston being provided with inclined slots spacing the piston skirts from the piston head and having enlarged terminal extensions spacing the side portions of the supporting walls from the piston head, said inclined slots being arranged to form rim. like flanges depending from the piston head at the said slots and adapted to prevent excessive splashes of lubricant Vfrom splashing directly through the slots.

'7. A piston including a piston head comprising a top wall, a depending peripheral wall and an annular partition wall extending inwardly from the peripheral wall and spaced from the top wall, vertical supporting walls depending from the annular partition wall of the piston head and having outwardly diverging side portions forming exterior pockets, wrist pin bosses arranged in the pockets and disposed exteriorly of the piston, piston skirts connecting the vertical supporting Walls, said piston being provided with inclined slots spacing the piston skirts from the piston head and having enlarged terminal extensions spacing the side portions of the supporting walls from the piston head, said inclined slots being arranged to form rim like flanges depending from the piston head at the said slots and adapted to prevent excessive splashes of lubricant from splashing directly through the slots, and vertical reinforcing and expansion controlling webs formed integral with the annular partition wall and with the supporting walls and tying the said parts together and maintaining the wrist pin bosses in alignment at all times.

8. A piston including a piston head comprising a top wall, a depending peripheral wall and a transverse partition wall extending inwardly fromthe peripheral wall and spaced from the top'wall, supporting walls depending from the piston head and having outwardly diverging side portions forming exterior pockets, aligned wrist pin bosses formed integral with said supporting walls and extending outwardly therefrom into the exterior pockets, circumferentially spaced piston skirts having their side edges integrally connected'tothe outer side edges of the diverging side portions of said supporting walls, and reinforcing and temperature controlling members forming integral with the wrist pin bosses and the transverse partition wall and tying said parts together and maintaining the wrist pin bosses go in alignment at all times.

FRANK MALINA.

CERTIFICATE OF CORRECTION.

Patent No. 2,177 57b. 1 October 2h, 1959.

FRANK MALINA.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, second column, line 1h, before the word "maintain" insert and; page 2, first column, line 18, for "adopted" read 7 adapted; page 5, first column, line 56, for "integraly" read integrally; page LL, second column, line 18 claim 8, for "forming" read formed; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 21st day of November, A. D. 1959.

Henry Van Arsdale,

(Seal) Acting Commissioner of Patents. 

